I have a large workbook - 8 megs in xls. I saved it as an XLSM file,
and it reduced the size to 2 m. Cool, I thought. I opened and ran
the workbook without difficulty in Excel 97, 2003, and 2007. Then I
send it out to others. When some of them opened it, the start-up
macros crashed, and the program would not run. After long telephone
conversations, it appears as though there are 2 copies active, both
with the same name? Not sure. In any event, the type of error
messages that pop up are the kind that happen when there are two
workbooks open. I had protected the macros by tying the statements to
'thisworkbook.sheets..." throughout, and thought I was running safe.

Those same people (there are 5 of them using it this weekend) all are
having intermittent problems - sometimes it opens and runs fine -
sometimes it does not open properly and those error messages pop up,
and the program displays the VBA sections.

I could set the macros to ignore errors, but I may be causing even
more problems. I just do not know, and my time clock is ticking, as
the program is used every weekend between now and Thanksgiving, so I
do not have much time for trial and error work.

So, today I sent the program out in XLS 2003 workbook format to see if
that solves it, but I do not grasp what is happening. I do not yet
know if that solution is what I should do or not. Can anyone tell me
what could be wrong?